The preparation of diazaspirodecan-2-ones named (in accordance with Bielstein nomenclature) 8-[{1-(3,5-Bis-(trifluoromethyl)phenyl)-ethoxy}methyl]-8-phenyl-1,7-diazaspiro[4.5]decan-2-one, for example, (5S,8S)-8-[{(1R)-1-(3,5-Bis-(trifluoromethyl)phenyl)-ethoxy}methyl]-8-phenyl-1,7-diazaspiro[4.5]decan-2-one (the compound of Formula I) is disclosed in published U.S. Pat. No. 7,049,320 issued May 23, 2006 (the '320 patent), which is incorporated herein by reference in its entirety.

The compounds disclosed in the '320 patent are classified as Tachykinin compounds, and are antagonists of neuropeptide neurokinin-1 receptors (the “NK-1” receptor antagonists). “NK-1” receptor antagonists have been shown to be useful therapeutic agents. For example, U.S. Pat. No. 5,760,018 (1998) describes some “NK-1” receptor antagonists as useful in the treatment of pain, inflammation, migraine and emesis (vomiting), and each of U.S. Pat. No. 5,620,989 (1997), WO 95/19344 (1995), WO 94/13639 (1994), and WO 94/10165 (1994) have described additional “NK-1” receptor antagonists which are useful in the treatment of treatment of pain, nociception and inflammation. Additional NK1 receptor antagonists are described in Wu et al, Tetrahedron 56, 3043-3051 (2000); Rombouts et al, Tetrahedron Letters 42, 7397-7399 (2001); and Rogiers et al, Tetrahedron, 57, 8971-8981 (2001). Among many compounds disclosed in the abovementioned '320 patent are several novel diazaspirodecan-2-ones, including the compound of Formula I, which is believed to be useful in the treatment of nausea and emesis associated with chemotherapy treatments (Chemotherapy-induced nausea and emesis, CINE). Emesis has been a problem in chemotherapy. Chemotherapeutic agents, for example, cisplatin carboplatin and temozolomide have been associated with both acute and delayed onset nausea and vomiting. It is known to administer chemotherapeutic agents with an anti-emetic, for example, as described in U.S. Pat. No. 5,939,098, which describes coadministration of temozolomide and with ondansetron, however such therapy is not effective in preventing delayed onset nausea and vomiting.
Compounds which have been identified as having therapeutic activity must be provided in a formulation suitable for administration to a patient in need of the therapeutic properties of the compound. In general, dosage forms suitable for oral administration are preferred due to the ease of administration, negligible invasiveness of the administrative procedure, and the convenience of providing the medicament in a variety of discrete dosage sizes. In general it is preferred to provide a solid oral dosage form which administers the therapeutic agent to a recipient through the gastrointestinal tract.